GDP measures summary value of goods and services generated in a relevant country or region. A region's gross domestic product, or GDP, is one of the ways for measuring the size of its economy. Expenditure approach - Total expenditures on all finished goods and services produced within the economy. Calculation: GDP using the expenditure approach is derived as the sum of all final expenditures, changes in inventories and exports of goods and services less imports of goods and services. Market influence of GDP Unexpectedly high quarterly GDP growth is perceived to be potentially inflationary if the economy is close to full capacity; this, in turn, causes bond prices to drop and yields and interest rates to rise. Where the stock market is concerned on one side higher than expected growth leads to higher profits and that's good for the stock market.